iPhone 3G incoming call only vibrates once?

[abijnk]

I have my phone on vibrate, and someone just called me. Weird thing is that it only vibrated ONCE! That was it! I had it sitting in front of me, so I was able to recognize that it was a phone call and not and email or txt message. Has anyone else had this problem? My first gen phone would vibrate until either I picked up or the call went to voicemail. Is there some setting I am missing here?

 

[Phil A.]

I had some weird issues with vibrate in that it stopped working completely. I fixed it by giving my phone a good slap on the back (after a full restore didn't do anything). I think my problem was caused by the vibration weight catching on something that stopped it turning, so it could be something similar with yours.
Because of the stock issues, I'm not going to even try and replace mine at the moment, but if it recurs then i'll have to take it back for a new one